ABSTRACT We propose an Older Americans Independence Center (OAIC) at Northwestern University. Its mission will be to: Generate innovative research that will enhance primary care for medically complex, older adults with multiple chronic conditions (MCC) to achieve optimal health, function, independence and quality of life. The Northwestern OAIC will catalyze research on: i) identifying modifiable clinical, healthcare system, and social environmental determinants of chronic disease outcomes, physical and mental health, and quality of life for older adults with MCC - especially those with frailty; ii) developing novel, practical, and scalable primary care management strategies that align with patient priorities, improve health outcomes and maintain independence for this vulnerable, at-risk, older adult population. The specific aims of the Northwestern OAIC are to: Aim 1 Formalize a comprehensive, multidisciplinary, aging research program dedicated to improving healthcare, functional independence, and quality of life for older adults with MCC. Aim 2 Expand Northwestern training and mentoring activities to develop future leaders in geriatrics and aging research who will transform healthcare to meet the needs of older adults with MCC. Aim 3 Stimulate applied research on the innovative design of primary care models that align with the priorities of older adults with MCC through aging-specific research resources and expertise in healthcare system & technology design (`Design Core'), patient-reported outcomes measurement (`Measurement Core') and quantitative & qualitative data analytics (`Analytics Core'). With strong institutional support and established infrastructure, we will organize internationally-recognized aging research faculty at Northwestern and establish a formal presence as a collaborative center on aging. Junior faculty with aging and MCC-related research interests will participate as mentored scientists; our OAIC will help them establish a successful career trajectory as independent investigators. Three essential Resource Cores (Design, Measurement, Analytics) will generate new methodological approaches for addressing MCC in primary care and facilitate designing and testing health system interventions via pilot and developmental projects, and through the use of an extensive portfolio of ongoing external studies. An Information Dissemination Core will leverage broad regional and national primary care networks to share findings, proactively seek collaborations, and find economies of scale in research and training activities among other OAICs and NIA centers. The Northwestern OAIC will introduce a timely and highly complementary area of focus, while bringing the greater Chicago community and Illinois into the national Pepper Center network.